Four new Antarctic holothuroid species are described for specimens from Admiralty Bay in King George Island. A new genus Dendrelasia O’Loughlin is erected for new cucumariid species Dendrelasia sicinski with dendrochirotid body form and elasipodid type spinous rod ossicles. Cucumariid Staurocucumis krzysztofi has bowl ossicles predominantly with marginal teeth. Provisionally−assigned thyonid Allothyone presleri has table ossicles with spires comprising predominantly four pillars. Molpadiid Molpadia magdae has a prickly cover of irregular table ossicle spires and fusiform table discs in both body wall and tail. Staurocucumis liouvillei (Vaney) is a “species complex”.